Oil well pump

ABSTRACT

An oil well subsurface pump comprising a plunger reciprocally disposed within a working barrel and having check valve means carried thereby. Piston rings are provided on the outer periphery of the plunger for engaging the inner periphery of the working barrel during reciprocation of the plunger which precludes bypassing of the plunger by the well fluid and permits a pumping action upon each stroke of the pump without slippage for greatly increasing the pumping efficiency. The piston rings are &#39;&#39;&#39;&#39;regular&#39;&#39;&#39;&#39; rings as opposed to eccentric rings, and are provided with a central bore substantially concentric with the outer diameter thereof for assuring an efficient sealing action during reciprocation of the pump plunger. In addition, a plurality of jets are provided at the upper end of the plunger for washing the plunger during the strokes thereof for reducing or substantially precluding accumulation of sand, or the like.

United States Patent 1 91 1111 3,910,730

Gage Oct. 7, 1975 [54] OIL WELL PUMP 3,586,464 6/1971 Crowe et al. 417/554 [76] Inventor: Lonnie L. Gage, Rte. 3, Box 158, I

Walters Ok1a 73572 Primary ExamznerW1ll1am L. Freeh [22] Filed: Feb. 22, 1974 l 4 28 [57] ABSTRACT 21 A N 4 5 5 1 pp An oil well subsurface pump comprising a plunger re- Related US. Application Data ciprocally disposed within a working barrel and having [63] Continuation-impart of s N 301,832,0 30 check valve means carried thereby. Piston rings are 1972, abandoned. provided on the outer periphery of the plunger for engaging the inner periphery of the working barrel dur- [52] US. Cl. 417/554 ing reciprocation of the plunger which precludes by- [51] Int. Cl. F04B 21/04 passing of the plunger by the well fluid and permits a [58] Field of Search 417/554; 277/173 pumping action upon each stroke of the pump without slippage for greatly increasing the pumping efficiency. [56] References Cited The piston rings are regular rings as opposed to ec UNITED STATES PATENTS centric rings, and are provided with a central bore 654,316 7/1900 Lewis 417/554 Substantially V i the Outer. diameier 1,060 622 5/1913 Owen I 417,173 thereof for assurmg an efficrent sealing action during 1,588,705 6/1926 Cope et al. 417/545 reciprocation 0f the P p P In addition, a P 1,703,354 2/1929 Nevill 417/554 rality of j are pr vi e at the upper end of the 1,777,959 10/1930 Budlong 1 277/173 plunger for washing the plunger during the strokes 1,785,334 12/1930 K g 4l7/554 thereof for reducing or substantially precluding accu- Harbisonnf. mulation of and or the like 2,745,660 5/1956 Delahay 277/173 3,168,052 2/1965 Pate 417/554 7 Claims, 5 Drawing Figures H2 7 I14 IIB Z I g 1 I04 1 #142 *IZO US. Patent Oct. 7,1975 Sheet 1 of 3 3,910,730

US. Patent Oct. 7,1975

as wig K ae% z US. Patent Oct. 7,1975 Sheath 3,910,730

on. WELL PUMP CROSS-REFERENCE TO RELATED APPLICATIONS This application is an improvement over the oil well pump disclosed in my co-pending application Ser. No. 429,542, filed Jan. 2, I974, and is a continuation-inpart of my co-pending application Ser. No. 301,832, filed Oct. 30, 1972 now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to improvements in'oil well pumps and more particularly, but not by way of limitation, to a reciprocal plunger type subsurface pump.

2. Description of the Prior Art In producing oil wells it is common practice to provide a pump at the bottom of the well bore or at least down the well bore in the producing formation. The pump is normally actuated by reciprocating of the pump plunger by sucker rods which extend through the well bore from a reciprocating device at the surface of the ground and into connection with the pump. The reciprocating device at the surface is usually a horse-head type pump and alternately raises and lowers the string of sucker rods in the well bore. Subsurface pumps have long presented many problems in lifting of the well fluid to the surface of the ground. For example, most pumps presently available have an inner barrel or plunger 2 /2 feet to 8 feet long which cause friction and drag on the plunger as the plunger reciprocates within the working barrel. As a result it is usually necessary to load the pump by the weight of the rods pushing down on the plunger. If the plunger does not move freely, the plunger may not have a full stroke, thus reducing pumping efficiency. In addition, many of the subsurface pumps have slippage in the operation of the plunger and require several strokes of the pump before I ing bypassing of the plunger by the well fluid. The pisa sufficient load is applied to the pump for starting the 1 pumping action. Also, many well fluids contain sand and other foreign particles which greatly hinder the operation of the subsurface pump and frequently damage the working parts thereof. The pumping of heavy viscous fluids also presents a problem to the usual pump available today.

SUMMARY OF THE INVENTION plunger or piston is disposed within a working barrel,

with suitable check valve means carried by the plunger for admitting the well fluid to the interior thereof during reciprocation of the plunger. The plunger is suitably connected with the usual sucker rods for reciprocation within the working barrel. The plunger is preferably only 9 to 12 inches long with a central bore of a maximum diameter depending upon the outer diameter of the plunger, which, of course, depends upon the size of the working barrel with which the pump is to be utilized. Thus, the pump will load freer and friction and drag will be reduced. Piston rings of the common well known regular type used in an automobile engine are ton rings are provided with a central bore substantially concentric with the outer circumference thereof for assuring an efficient seal during reciprocation of the pump. This assures a quick and efficient loading of the pump whereby pumping action is produced with the initial stroke of the plunger and the pump will pump approximately 20 per cent more fluid than possible with presently available pumps of this type. Thus, viscous well fluids as well as sandy well fluid may be efficiently elevated 'to the surface of the ground by the novel pumping apparatus. In addition, a plurality of ports are provided in the proximity of the upper end of the pump plunger for washing the plunger during reciprocation thereof for substantially precluding build up of sand or other debris during use of the pump.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings in detail, and particularly FIG. 1, reference character 10 generally indicates a subsurface pump comprising a plunger assembly 12 reciprocally disposed within a working barrel 14. The working barrel 14 is preferably set within a well tubing (not shown) by a suitable packer (not shown), or the like, as is well known, and in such a manner that the pump 10 is disposed in the proximity of or within a producing formation (not shown) of the well bore (not shown). However, it is to be noted that it may be desirable to retain the pump plungerassembly l2 stationary and reciprocate the working barrel 14 with respect thereto during the pumping operation.

The plunger assembly 12 comprises a main sleeve or housing 16 having a central bore 18 extending longitudinally therethrough to provide a fluid passageway through the pump 10. The upper end of the sleeve 16 is provided with a reduced neck portion 20 having an internally threaded portion 22 for threaded connection with the lower end of a suitable coupling member 14 which in turn is suitably secured to the lowermost sucker rod (not shown) of the sucker rod string extending to the surface of the ground. Of course, the sleeve 16 may be secured directly to the lowermost sucker rod, if desired, or may be secured to the sucker rods in any suitable manner in lieu of the coupling 24. As shown herein, the pump 10 is utilized in combination with solid sucker rods, but it will be apparent that the device may be utilized with hollow sucker rods, if desired.

The neck 20 is provided with an inwardly directed annular shoulder 26 spaced slightly below the threaded portion 22 for receiving a plate or disc 28 thereon. The

lower end of the coupling 24 bears against the upper surface of the plate 28 for retaining the plate 28 securely in position against the shoulder 26. A centrally disposed rod or stem 30 is secured to or integral with the plate 28 and extends downwardly therefrom as viewed in FIG. 1 through the bore 18 for a purpose as will be hereinafter set forth. Whereas the disc 28, as shown herein, is solid and particularly designed for use with solid sucker rods, it is to be understood that the disc 28 may be of a web or spider type configuration for permitting fluid to flow through in the event hollow sucker rods are used.

A plurality of circumferentially spaced ports or bores 32 are provided in the neck spaced substantially immediately below the shoulder 26 for providing communication between the bore 18 and the annular space 34 between the sucker rods and working barrel 14. In the event hollow sucker rods are used, it may be desirable to eliminate the ports 32 in order that the well fluid will move from the bore 18 upwardly through the hollow sucker rods during the pumping action of the pump 10 as will be hereinafter set forth.

The lower end of the bore 18 is provided with an inwardly directed annular shoulder 36 for receiving a valve seat 38 thereagainst. The bore 18 is threaded below the shoulder 38, as shown at 40, for receiving a suitable coupling or retainer sleeve 42 therein. The retainer sleeve 42 bears against the valve seat 38 for securely retaining the valve seat in position against the shoulder 36. A suitable ball member 44 is loosely disposed in the bore 18 and cooperates with the valve seat 38 to provide a normally closed check valve for the pump 10, for a purpose as will be hereinafter set forth.

A plurality of longitudinally spaced annular grooves 46 are provided on the outer periphery of the sleeve 16 for receiving piston rings 48 therein. Two sets of the grooves 46 are depicted in FIG. 1, with one set of grooves being disposed in the proximity of the upper end of the sleeve 16 and a second set of grooves spaced therefrom and disposed in the proximity of the lower end of the sleeve 16. However, it is to be understood that substantially any desired number of the grooves 46 maybe provided on the outer periphery of the sleeve 16, and the grooves 46 may be spaced therealong for spacing the piston rings 48 in substantially any suitable or desirable manner in accordance with the overall length of the plunger 12 and the particular working requirements for the pumping apparatus 10.

The piston rings 48 are preferably of the split or snap ring type normally used in connection with automobile engine pistons and are of a size for wiping or engaging the inner periphery of the working barrel 14 during reciprocation of the plunger assembly 12, as will be hereinafter set forth. It is to be noted that whereas the rings 48 depicted in the drawings comprise a pair of relatively narrow rings 48 in each groove 46, it may be desirable to provide a single relatively wide ring in each of the grooves 46. However, it is usually preferable to provide a sufficient number of narrow rings in order to make a tighter packing with less friction than a smaller number of wider rings. As a practical matter, two narrow rings in each groove may be found to provide better results than one wide ring.

As hereinbefore set forth, the piston rings 48 are preferably of the type normally used in connection with automobile pistons which are usually metallic and constructed in a manner for being constantly urged radially outwardly. For example, the rings 48 such as might be utilized with a one and one half inch diameter plunger, and as purchased from a manufacturer, may be identified as folows:

l X 500 X 1225 X 063 X 073 step cut 5/32 inch step and a similar ring 48 such as might be utilized with a 2 inch diameter plunger and as purchased from a manufacturer may be identified as follows:

2000 X 124 X 1225 X 080 X 090 step cut 5/32 inch step.

With regard to the ring for the 1 /2 inch diameter plunger, the identifications set forth above may be interpreted as follows:

1 X 500 indicates that the ring is for use with a piston having a diameter of l /zinches.

124 indicates the width of the ring, in thousandths of an inch.

1225 indicates the depth of the ring, in thousandths of an inch.

063 indicates the clearance between the internal diameter of the ring and the bottom of the ring groove in thousandths of an inch.

073 indicates the clearance between the internal diameter of the ring and the bottom of the groove, in thousandths of an inch, when the ring is in compression.

Step cut indicates that the ring is provided with overlapping type ends of a step cut configuration.

5/32 inch step indicates that the dimension of the step at the ends of the ring is 5/32 inch, indicating the overall dimension of expansion for the ring before a complete separation beween the ends occurs (in this instance, the ring ends can move through a combined distance of 5/16 inch before complete separation of the ring ends occurs.)

In addition, these rings usually have a 0.013 inch compression factor, which means that the ring will function efficiently until it has become worn sufficiently to reduce its outer dimensions by more than 0.013 inch.

It will be apparent that a similar analysis may be made of the identification of the ring 48 for the piston having a 2 inch outer diameter.

During operation of an automobile engine, it is considered that the engine lubricating oil circulates around the piston rings during reciprocation of the pistons within the cylinders. The lubricating oil is thought to flow through the slight clearance between the internal diameter of the rings and the bottom of the ring groove, thus filling the area therebetween and upon compression of the rings, the oil in the groove provides an additional pressure for forcing the rings radially outward into an efficient sealing engagement with the walls of the cylinder in which the piston is reciprocating. It is considered that this same action occurs during use of the pump 10, which may account for the extremely improved results with the use of the pump.

in addition, it is to be noted that automobile piston rings, such as the rings 48 are regular rings, as indicated in the drawings, having the internal bore thereof concentric with the outer circumference thereof as opposed to any eccentric configuration. This means that the internal bore of the rings is circular and not elongated or oval, thus assuring that the plunger 12 will be efficiently maintained in a centered or concentric position within the working barrel 14 during reciprocation of the plunger therein.

If desired a wiper ring (not shown) may be provided on the outer periphery of the sleeve 16 spaced below the grooves 46. The wiper ring 40 may be constructed from a suitable flexible material, such as rubber neoprene, or the like, for wiping the inner periphery of the working barrel 14 during reciprocation of the plunger assembly 12.

The lower end of the sleeve 16 is open to or in communication with the fluid reservoir (not shown) provided in the well tubing (not shown), or in the well bore (not shown) above the usual standing valve (not shown) through the retainer sleeve 42. The standing valve is normally provided in the well tubing (not shown) below the working barrel 14 and is in communication with the fluid to be produced from the well bore, as is well known.

In operation, the working barrel 14 is set in the well tubing (not shown) in the proximity of the producing formation in any well known manner, and preferably above the standing valve (not shown). The pump plunger assembly 12 is reciprocated within the working barrel 14 by the normal sucker rods (not shown) in the usual manner. On the upstroke of the plunger assembly 12, a suction is created in the well tubing above the standing valve for opening the standing valve and pulling a quantity of the well fluid into the interior of the well tubing. It will also be apparent that the ball 44 will be urged against the valve seat 38 upon the upstroke of the plunger assembly 12 for closing of the ball check valve. On the downstroke of the plunger assembly 12, the pressure of the fluid in the well tubing will raise the ball 14 from the valve seat 38 for opening of the ball check valve (sometimes called a travelling valve). The well fluid will move through the open valve and into the bore 18 for discharge through the ports 36 into the annular chamber 34 and into the working barrel 14 above the sleeve 16. Of course, continued reciprocation of the plunger assembly 12 causes the fluid within the working barrel 14 to rise therein, and suitable ports (not shown) are usually provided in the working barrel 14 for directing the fluid into the interior of the well tubing above the pump 10, as is well known in this type of pumping apparatus.

Of course, the upward movement of the ball 44 is limited by the engagement of the ball 44 with the lowermost end of the stem or rod 30. The rod 30 may be of substantially any predetermined length for regulating the movement of the ball 44 as desired. In the event it is preferable to provide for a maximum of travel for the ball 44 within the bore 18, the stem 30 may be relatively short. In the event it is preferable to permit only a limited amount of travel for the ball 44, the stem 30 may be relatively long.

Of course, the piston rings 46 move against the inner periphery of the working barrel 14 during reciprocation of the plunger assembly 12 in much the same manner as the piston rings of a piston in a cylinder of an automobile internal combustion engine. The engagement of the piston rings 48 with the inner periphery of the working barrel 14 substantially precludes any leakage of the well fluid between the sleeve 16 and the working barrel 14 whereby each stroke of the pump plunger assembly l2 delivers fluid into the working barrel 13 above the plunger assembly 12 with substantially no slippage between the plunger and the working barrel. Furthermore, in the event a wiper ring is provided, the wiper ring will wipe the inner periphery of the working barrel 14 during reciprocation of the plunger assembly 12. In addition, the fluid moving through the ports 32 will flush the upper end of the sleeve 16 or wash the upper end thereof for substantially precluding any build up of sand or other foreing particles on top of the sleeve 16, thus substantially precluding sanding up of the pump 10.

In the event hollow sucker rods are utilized in lieu of solid sucker rods, it may be desirable to eliminate the ports 32 and move the fluid upwardly from the bore 18, through the web type plate 28 and upwardly through the hollow sucker rods for elevating the well fluid to the surface of the ground.

It will be apparent that whereas the operation of the pump 10 is set forth herein for the arrangement wherein the plunger assembly 12 is reciprocated within a stationary working barrel, the operation of the pump 10 is generally similar in such instances wherein the plunger assembly 12 is held stationary and the working barrel 14 is reciprocated.

Referring now to FIG. 2, a similar subsurface oil well pump is generally indicated at 50. The pump 50 comprises a sleeve or housing 52 reciprocally disposed within a working barrel 54. The working barrel 54 is preferably set within the well tubing (not shown) in the manner as hereinbefore set'forth, with the pumping apparatus 50 being disposed in the proximity of the producing formation in the well bore. The sleeve 52 is provided with a longitudinally extending central bore 56 providing a fluid passageway therethrough. The upper end of the sleeve 52 is provided with a reduced neck portion 57 having an internally threaded portion 58 for connection with the lowermost sucker rod 60, or for connection with a suitable coupling member (not shown) which in turn is connected with the lowermost sucker rod as hereinbefore set forth. A plurality of circumferentially spaced ports or bores 62 are provided in the reduced neck 57 and spaced below the threaded portion 58 for providing communication between the bore 56 and the annular space 64 between the sucker rods 60 and the working barrel 54.

The lower end of the sleve 52 is threaded as shown at 66 for receiving a sleeve member 68 thereon. The sleeve 68 is provided with a central bore 70 extending longitudinally therethrough and in open communication with the bore 56. The bore 70 is preferably bellied out as shown in FIG. 2 for providing the greatest possible cross-sectional area for the bore 70. In addition, a suitable liner (not shown) may be provided for the bore 70, if desired, with the liner preferably being constructed from a suitable spring type material and having slotted sidewalls for facilitating insertion thereof into the bore 70, for a purpose as well be hereinafter set forth. The bore 70 is reduced to provide an inwardly directed annular shoulder 72 in the proximity of the lower end thereof for receiving a valve seat member 74 thereagainst. The lower end of the bore 70 is preferably threaded, as shown at 76, for receiving a retaining sleeve 78 therein. The retaining sleeve 78 bears against the valve seat 74 for retaining the valve seat securely against the shoulder 72.

A ball member 80 is loosely disposed in the bore 70 and cooperates with the valve seat 74 for providing a normally closed check valve for the pumping apparatus 50. A pin member 82 extends transversely across the bore 70 in the proximity of the upper end thereof, and may be secured therein in any well known manner,

such as by a press fit within a pair of aligned bores 84 and 86 provided in the sidewalls of the sleeve 68. The bar 82 provides a stop or limit for the upward movement of the ball 80 during operation of the pump 50, as will be hereinafter set forth.

A plurality of annular grooves 88 similar to the grooves 46 are longitudinally spaced on the outer periphery of the sleeve 54 for receiving piston rings 90 therein similar to the rings 48. Whereas four of the grooves 88 are depicted in FIG. 2, it is to be understood that substantially any desired number and spacing of the grooves 88 may be provided in accordance with the working conditions and operating circumstances of the pump 50. In some instances, a single groove 88 having having the rings 90 therein have been found to be suff1- cient.

It may be desirable to provide a standard or common sleeve 52 with a minimum number of the grooves 88 and piston rings 90 provided thereon or efficient use in a pumping situation, and provide a plurality of interchangeable sleeves 68 for use with the standard or common sleeve 52, with the interchangeable sleeves 68 being provided with a variable number of the grooves 92 and piston rings 94. Under these conditions, a plunger assembly may be provided for meeting substantially any pumping conditions by selecting the sleeve 68 having the proper number of rings 94 for use in combination with the rings 90 of the standard sleeve 52. Thus, a variety of pumping assemblies may be provided with the use of a minimum number of parts in stock.

In addition, a suitable wiper ring (not shown) may be provided on the outer periphery of the sleeve 68 spaced below the rings 94. The wiper ring will wipe the inner periphery of the working barrel 54 during reciprocation of the sleeve 68 within the working barrel 54.

The operation of the pumping apparatus is generally similar to the operation of the pumping apparatus 10. The working barrel 54 is set in the well buting (not shown) in the proximity of the producing formation, with the usual standing valve (not shown) being provided in the well tubing below the working barrel 54 and in communication with the fluid to be produced from the well bore, as hereinbefore set forth. The sleeve 52 is conneeted with the lowermost sucker rod whereby the sleeve 52 may be reciprocated within the working barrel 54 in the usual manner, and the bores 70 and 56 are in communication with the well fluid through the retainer sleeve 78 as hereinbefore set forth. On the upstroke of the sleeves 52 and 66, a suction is created in the well tubing above the standing valve for opening thereof and pulling a quantity of the well fluid into the interior of the well tubing. It will be apparent that the ball 80 is urged against the valve seat 74 on the upstroke of the sleeves 52 and 68 for closing the ball valve. On the downstroke of the sleeves 52 and 68 the pressure of the fluid in the well tubing raises the ball 80 from the valve seat 74 for opening the valve (often referred to as a travelling valve) whereby the well fluid is introduced into the bores 70 and 56. Of course, continued reciprocation of the plunger sleeves 52 and 68 causes the fluid within the bores 70 and 56 to rise therein for filling the sleeves 68 and 52 and for discharge of the fluid through the bores 62 into the annular space 64. Continued reciprocation of the sleeves 52 and 68 will elevate the well fluid through the working barrel 54 and well tubing to the surface of the well as is well known.

The movement of the fluid through the bores 62 provides a washing or flushing action for substantially precluding any build up of sand, or the like, above the sleeve 52, thus substantially precluding sanding up" of the pumping apparatus 50.

Of course, in the event hollow sucker rods (not shown) are utilized in lieu of the solid sucker rods 60, it may be desirable to eliminate the bores 62 whereby the well fluid will be delivered to the surface of the ground through the hollow sucker rods rather than through the well tubing.

As hereinbefore set forth, the piston rings and 94 engage the inner periphery of the working barrel 54 in much the same manner as the piston rings of an automobile engine engage the cylinder walls. The piston rings 90 and 94 assure that substantially no well fluid will bypass the sleeves 52 and 68, thus providing an efficient pumping action for the pump 50.

The pump 50 may be utilized as hereinbefore set forth, or may be similarly utilized in instances wherein the sleeves 52 and 68 are held stationary, and the working barrel 54 is reciprocated.

In addition, it will be readily apparent that the sleeve 68 may be utilized at the lower end of the tubing string (not shown) in lieu of the normal cage (not shown) provided for the usual standing valve (not shown). The utilization of the transversely extending pin 82 for limiting the upward movement of the ball member (not shown) of the standing valve (not shown) will eliminate many problems in the operation of the usual standing valve. Thus, the sleeve 68, either having the piston rings 94 provided thereon, or with a smooth or plain outer periphery may be utilized for increasing the efficiency of the usual standing valve in a producing oil well.

Referring now to FIGS. 3, 4 and 5, a modified subsurface pump apparatus is generally indicated at which is similar to the pumps 10 and 52. The pump 100 comprises a sleeve or housing 102 reciprocally disposed within a stationary working barrel 104 in the same manner as hereinbefore set forth in connection with the pumps 10 and 50. It is to be understood, however, that the plunger 102 may remain stationary while the working barrel 104 is reciprocated, if desired, with the same efficient pumping results.

The working barrel 104 is preferably set within the well tubing (not shown) in the manner as hereinbefore set forth, with the pumping apparatus 100 being disposed in the proximity of the producing formation in the well bore. The sleeve 102 is provided with a longitudinally extending central bore 106 providing a fluid passageway therethrough. The upper end of the sleeve 102 may be internally threaded as shown at 108 for receiving one end of a cylindrical insert member 110 therein. The opposite end of the insert member 110 is internally threaded at 112 for connection with the lowermost sucker rod 114, or for connection with a suitable coupling member (not shown) which in turn is connected with the lowermost sucker rod as hereinbefore set forth.

The insert member 110 is in open communication with the bore 106, and is provided with a plurality of circumferentially spaced bores or ports 116 spaced above the threaded portion 108 for providing communication between the bore 106 and the annular space 118 between the sucker rods 114 and the working barrel 104.

The lower end of the sleeve 102 may be internally threaded, as shown at 120, for connection with a coupling member 122, or the like, as hereinbefore set forth. An annular valve seat insert member 124 is disposed in the bore 106 substantially immediately above the coupling member 122 and may be secured therein against longitudinal movement in any suitable manner, such as by a set screw 126 extending through the sidewalls of the sleeve 102 and engagable with an annular recess 128 provided on the outer periphery of theinsert or valve seat 124. A ball member 130 similar to the balls 44 and 80 is loosely disposed in the bore 106 and cooperates with the valve seat 124 for providing a normally closed check valve for the pumping apparatus 100. A stop element generally indicated at 132 is disposed in the upper portion of the bore 106, as shown in FIG. 3, and is preferably in engagement with the lowermost end of the insert member 110 for limiting the upward movement of the ball member 130 during reciprocation of the plunger sleeve 102 in the working barrel 104, as hereinbefore set forth.

The stop element 132 comprises a plurality of tension spring elements 134 which may be similar to the tension spring members utilized in the Halliburton R-4 Treating-Production Packer manufactured by Halliburton Services. As shown herein, three of the tension spring members 134 are utilized, each of which are provided with arcuate elements 136 and 138 at the opposite ends thereof. Three of the arcuate elements 136 disposed in end to end or abutting relationship form an annular element, and similarly three of the arcuate elements 138 disposed in end to end or abutting relationship form an annular element. Each of the segments 136 and 138 is provided with a groove 137 and 139, respectively, on the outer periphery thereof which cooperate with the grooves of the corresponding segments 136 and 138 for forming annular grooves in order that snap rings 140 and 141, or the like, may be disposed in the annular grooves 137 and 139, respectively, for retaining the arcuate segments 136 and the arcuate segments 138 in said annular configuration, thus providing the assembled stop element 132.

The spring elements 134 are particularly designed and constructed for constantly applying a radially outward force against the periphery of the bore 106 for retaining the stop element 132 in the preselected longitudinal position within the bore 106. Thus, it will be apparent that the length of travel for the ball 130 may be limited by the selected positioning of the stop element 132 within the bore 132.

A plurality of annular grooves 142 similar to the grooves 46 and 88 are longitudinally spaced on the outer periphery of the sleeve 102 for receiving piston rings 144 therein similar to the rings 90 and 48. Whereas four of the grooves 140 are depicted in the proximity of the upper end of the sleeve 102 and four grooves 140 are depicted in the proximity of the lower end of the sleeve 102, it will be apparent that substantially any desired number and spacing may be provided for the grooves 140, as hereinbefore set forth. Of course, it will be apparent that the stop element 132 may be of a unitary construction, if desired, rather than the segmental type construction depicted herein.

The operation of the pumping apparatus 100 is substantially as hereinbefore set forth in connection with the pumps and 50. One advantage of the pump 100 is the straight through construction of the bore 106 reduces the cost of construction, and the use of the independent insert member having the ports 116 therein facilitates the replacement of any Worn parts, and reduces the cost of construction and assembly of the pump 100.

From the foregoing it will be apparent that the present invention provides a novel subsurface pump for producing oil wells wherein a simple reciprocal plunger member is disposed within the working barrel. The usual travelling valve or check valve is carried by the plunger, and preferably disposed within the plunger, for facilitating admitting of the well fluid from the fluid reservoir in the well bore to the interior of the tubing string, or to the interior of the hollow sucker rod string, for advancing or lifting the well fluid to the surface of the ground. Piston rings similar to the piston rings of an automobile internal combustion engine are provided around the outer periphery of the pump plunger for engaging the innder periphery of the working barrel during operation of the pump. The piston rings substantially preclude leakage or bypassing of the well fluid between the plunger and the working barrel for providing an efficient pumping action on each stroke of the plunger. The novel pump is simple and efficient in operation and economical and durable in construction.

Whereas the present invention has been described in particular relation to the drawings attached hereto, it should be understood that other and further modifications, apart from those shown or suggested herein, may be made within the spirit and scope of this invention.

What is claimed is:

l. A subsurface well pump comprising a first elongated stationary tubular member in communication with a well fluid reservoir, a second elongated tubular member in communication with the well fluid and concentrically arranged with respect to the stationary tubular member and reciprocal with respect thereto, check valve means disposed within one of said tubular members to provide alternate open and closed positions for the pump during operation thereof, piston ring means provided on the outer periphery of one of said tubular members and engagable with the inner periphery of the other of said tubular members to provide a maximum fluid seal therebetween with a minimum of frictional drag for substantially precluding bypassing of the well fluid between the tubular members during operation of the pump, said piston ring means including at least one relatively thin annular metallic ring having the central bore thereof concentric with the outer circumference thereof, said valve means including valve seat means removably secured within said one tubular member, ball means loosely disposed within said one tubular member and cooperating with the valve seat means for providing said alternate open and closed positions for the pump, and limit means carried by one of said tubular members for limiting the movement of the ball means in one direction during operation of the pump while maintaining a maximum fluid flow through the pump, said limit means comprising tension spring means disposed within one of said tubular members and in a pressure engagement with the inner periphery thereof.

2. A subsurface well pump as set forth in claim 1, wherein said tension spring means comprises a plurality of circumferentially spaced tension springs secured together to provide a cage-like assembly for maintaining said maximum fluid flow through the pump.

3. A subsurface well pump as set forth in claim 2, wherein the piston ring means comprises first piston ring means disposed on the outer periphery of the first sleeve and second piston ring means disposed on the outer periphery of the second sleeve, and wherein said annular piston rings are relatively thin snap type rings as used on automobile internal combustion engine pistons.

4. A subsurface well pump as set forth in claim 1, wherein said one tubular member comprises an elongated sleeve member having a central bore extending longitudinally therethrough, a plurality of circumferentially spaced radially extending ports provided in the proximity of one end of the sleeve to provide communication between the bore and the exterior of the sleeve, said check valve being secured within the opposite end of the sleeve member for intermittently admitting the well fluid into the bore whereby the well fluid fills the bore and is discharged therefrom through the ports for elevating the well fluid to the surface of the well.

5. A subsurface well pump as set forth in claim 1, wherein said one tubular member comprises an elongated sleeve member having a central bore extending longitudinally therethrough, an insert member threadedly secured to one end of said sleeve member and having a plurality of circumferentially spaced radially extending ports provided therein, said check valve being secured within the opposite end of the sleeve member for intermittently admitting the well fluid into the bore whereby the well fluid fills the bore and is discharged therefrom through the ports for elevating the well fluids to the surface of the well.

6. A subsurface well pump as set forth in claim 1, wherein one of said tubular members is provided with a plurality of circumferentially spaced radially extending ports in the proximity of one end thereof, and said check valve means is secured within the opposite end of said tubular member, and the limit means comprises a disc member secured to said tubular member in spaced relation to the valve seat means and above the ports, and a rod member carried by the disc member and extending longitudinally through one of said tubular members in a direction toward the valve seat means for limiting the movement of the ball member during opening of the pump.

7. A subsurface well pump as set forth in claim 1, wherein the said one tubular member comprises a pair of sleeve members secured in end to end relation, central passageway means provided in each sleeve member and extending longitudinally therethrough to provide a fluid passageway, a plurality of circumferentially spaced radially extending ports provided in the sidewalls in the first of said sleeves to provide communication between the fluid passageway and the exterior of the sleeves, and said check valve means comprises a valve seat member secured within said second sleeve, a ball member loosely disposed in the bore of the second sleeve for cooperating with the valve seat to provide said alternate opened and closed positions for the pump, and said limit means comprises a transversely extending rod member secured in the bore of the second sleeve for limiting the movement of the ball member during opening of the pump. 

1. A subsurface well pump comprising a first elongated stationary tubular member in communication with a well fluid reservoir, a second elongated tubular member in communication with the well fluid and concentrically arranged with respect to the stationary tubular member and reciprocal with respect thereto, check valve means disposed within one of said tubular members to provide alternate open and closed positions for the pump during operation thereof, piston ring means provided on the outer periphery of one of said tubular members and engagable with the inner periphery of the other of said tubular members to provide a maximum fluid seal therebetween with a minimum of frictional drag for substantially precluding bypassing of the well fluid between the tubular members during operation of the pump, said piston ring means including at least one relatively thin annular metallic ring having the central bore thereof concentric with the outer circumference thereof, said valve means including valve seat means removably secured within said one tubular member, ball means loosely disposed within said one tubular member and cooperating with the valve seat means for providing said alternate open and closed positions for the pump, and limit means carried by one of said tubular members for limiting the movement of the ball means in one direction during operation of the pump while maintaining a maximum fluid flow through the pump, said limit means comprising tension spring means disposed within one of said tubular members and in a pressure engagement with the inner periphery thereof.
 2. A subsurface well pump as set forth in claim 1, wherein said tension spring means comprises a plurality of circumferentially spaced tension springs secured together to provide a cage-like assembly for maintaining said maximum fluid flow through the pump.
 3. A subsurface well pump as set forth in claim 2, wherein the piston ring means comprises first piston ring means dispOsed on the outer periphery of the first sleeve and second piston ring means disposed on the outer periphery of the second sleeve, and wherein said annular piston rings are relatively thin snap type rings as used on automobile internal combustion engine pistons.
 4. A subsurface well pump as set forth in claim 1, wherein said one tubular member comprises an elongated sleeve member having a central bore extending longitudinally therethrough, a plurality of circumferentially spaced radially extending ports provided in the proximity of one end of the sleeve to provide communication between the bore and the exterior of the sleeve, said check valve being secured within the opposite end of the sleeve member for intermittently admitting the well fluid into the bore whereby the well fluid fills the bore and is discharged therefrom through the ports for elevating the well fluid to the surface of the well.
 5. A subsurface well pump as set forth in claim 1, wherein said one tubular member comprises an elongated sleeve member having a central bore extending longitudinally therethrough, an insert member threadedly secured to one end of said sleeve member and having a plurality of circumferentially spaced radially extending ports provided therein, said check valve being secured within the opposite end of the sleeve member for intermittently admitting the well fluid into the bore whereby the well fluid fills the bore and is discharged therefrom through the ports for elevating the well fluids to the surface of the well.
 6. A subsurface well pump as set forth in claim 1, wherein one of said tubular members is provided with a plurality of circumferentially spaced radially extending ports in the proximity of one end thereof, and said check valve means is secured within the opposite end of said tubular member, and the limit means comprises a disc member secured to said tubular member in spaced relation to the valve seat means and above the ports, and a rod member carried by the disc member and extending longitudinally through one of said tubular members in a direction toward the valve seat means for limiting the movement of the ball member during opening of the pump.
 7. A subsurface well pump as set forth in claim 1, wherein the said one tubular member comprises a pair of sleeve members secured in end to end relation, central passageway means provided in each sleeve member and extending longitudinally therethrough to provide a fluid passageway, a plurality of circumferentially spaced radially extending ports provided in the sidewalls in the first of said sleeves to provide communication between the fluid passageway and the exterior of the sleeves, and said check valve means comprises a valve seat member secured within said second sleeve, a ball member loosely disposed in the bore of the second sleeve for cooperating with the valve seat to provide said alternate opened and closed positions for the pump, and said limit means comprises a transversely extending rod member secured in the bore of the second sleeve for limiting the movement of the ball member during opening of the pump. 